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Business segment data - Earnings data (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Segment Reporting Information [Line Items] |  |  |  |
Revenues | $ 94,972 | $ 92,995 | $ 277,212 | $ 276,517
Costs and Expenses: |  |  |  |
Interest expense | 1,261 | 1,214 | 3,771 | 3,760
Total costs and expenses | 79,136 | 81,223 | 236,788 | 237,380
Earnings before income taxes | 38,105 | 32,508 | 58,003 | 86,351
BNSF [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 6,013 | 5,920 | 17,458 | 17,344
BHE [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 7,293 | 7,323 | 20,042 | 20,068
Manufacturing [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 20,015 | 19,670 | 58,707 | 57,988
Service and Retailing [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 10,568 | 9,828 | 31,351 | 29,422
Pilot [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 10,879 | 10,623 | 31,396 | 36,101
McLane [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 12,960 | 12,527 | 37,375 | 37,098
Operating Businesses [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 94,237 | 92,809 | 274,998 | 276,165
Costs and Expenses: |  |  |  |
Interest expense | 1,327 | 1,272 | 3,952 | 3,712
Earnings before income taxes | 14,424 | 12,949 | 39,417 | 38,737
Operating Businesses [Member] | Insurance Group [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 26,181 | 26,664 | 77,804 | 77,332
Costs and Expenses: |  |  |  |
Losses and loss adjustment expenses ("LAE") | 13,735 | 15,163 | 42,454 | 42,718
Life, annuity and health benefits | 1,116 | 925 | 3,316 | 2,824
Other segment items | 4,451 | 4,948 | 13,335 | 12,769
Total costs and expenses | 19,302 | 21,036 | 59,105 | 58,311
Earnings before income taxes | 6,879 | 5,628 | 18,699 | 19,021
Operating Businesses [Member] | Insurance Group [Member] | Underwriting [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 22,445 | 22,055 | 66,444 | 65,482
Costs and Expenses: |  |  |  |
Losses and loss adjustment expenses ("LAE") | 13,735 | 15,163 | 42,454 | 42,718
Life, annuity and health benefits | 1,116 | 925 | 3,316 | 2,824
Other segment items | 4,431 | 4,933 | 13,255 | 12,733
Total costs and expenses | 19,282 | 21,021 | 59,025 | 58,275
Earnings before income taxes | 3,163 | 1,034 | 7,419 | 7,207
Operating Businesses [Member] | Insurance Group [Member] | Underwriting [Member] | GEICO [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 11,264 | 10,699 | 33,080 | 31,402
Costs and Expenses: |  |  |  |
Losses and loss adjustment expenses ("LAE") | 8,047 | 7,634 | 23,416 | 22,803
Other segment items | 1,444 | 1,032 | 3,897 | 2,852
Total costs and expenses | 9,491 | 8,666 | 27,313 | 25,655
Earnings before income taxes | 1,773 | 2,033 | 5,767 | 5,747
Operating Businesses [Member] | Insurance Group [Member] | Underwriting [Member] | BH Primary [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 4,711 | 4,685 | 13,965 | 13,882
Costs and Expenses: |  |  |  |
Losses and loss adjustment expenses ("LAE") | 2,842 | 4,066 | 9,487 | 9,971
Other segment items | 1,363 | 1,308 | 4,053 | 3,835
Total costs and expenses | 4,205 | 5,374 | 13,540 | 13,806
Earnings before income taxes | 506 | (689) | 425 | 76
Operating Businesses [Member] | Insurance Group [Member] | Underwriting [Member] | BHRG [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 6,470 | 6,671 | 19,399 | 20,198
Costs and Expenses: |  |  |  |
Losses and loss adjustment expenses ("LAE") | 2,846 | 3,463 | 9,551 | 9,944
Life, annuity and health benefits | 1,116 | 925 | 3,316 | 2,824
Other segment items | 1,624 | 2,593 | 5,305 | 6,046
Total costs and expenses | 5,586 | 6,981 | 18,172 | 18,814
Earnings before income taxes | 884 | (310) | 1,227 | 1,384
Operating Businesses [Member] | Insurance Group [Member] | Investment Income [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 3,736 | 4,609 | 11,360 | 11,850
Costs and Expenses: |  |  |  |
Other segment items | 20 | 15 | 80 | 36
Total costs and expenses | 20 | 15 | 80 | 36
Earnings before income taxes | 3,716 | 4,594 | 11,280 | 11,814
Operating Businesses [Member] | BNSF [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 6,039 | 5,940 | 17,528 | 17,405
Costs and Expenses: |  |  |  |
Compensation and benefits | 1,400 | 1,407 | 4,159 | 4,140
Fuel | 772 | 799 | 2,240 | 2,475
Depreciation and amortization | 684 | 644 | 2,034 | 1,964
Interest expense | 279 | 275 | 821 | 807
Other segment items | 992 | 969 | 2,950 | 3,032
Total costs and expenses | 4,127 | 4,094 | 12,204 | 12,418
Earnings before income taxes | 1,912 | 1,846 | 5,324 | 4,987
Operating Businesses [Member] | BHE [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 7,304 | 7,335 | 20,078 | 20,104
Costs and Expenses: |  |  |  |
Energy Cost of Sales | 1,876 | 1,902 | 4,841 | 5,099
Energy Operations and Maintenance | 1,473 | 1,342 | 4,114 | 4,139
Energy Depreciation and Amortization | 1,025 | 986 | 3,088 | 2,944
Real estate operating costs and expenses | 1,146 | 1,151 | 3,227 | 3,477
Interest expense | 658 | 630 | 1,968 | 1,900
Other segment items | 213 | 223 | 819 | 686
Total costs and expenses | 6,391 | 6,234 | 18,057 | 18,245
Earnings before income taxes | 913 | 1,101 | 2,021 | 1,859
Operating Businesses [Member] | Manufacturing [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 20,047 | 19,675 | 58,782 | 58,044
Costs and Expenses: |  |  |  |
Cost of sales and services | 12,848 | 12,801 | 38,157 | 38,091
Cost of leasing | 288 | 297 | 887 | 827
Interest expense | 303 | 264 | 886 | 657
Other segment items | 3,024 | 3,178 | 9,305 | 9,291
Total costs and expenses | 16,463 | 16,540 | 49,235 | 48,866
Earnings before income taxes | 3,584 | 3,135 | 9,547 | 9,178
Operating Businesses [Member] | Service and Retailing [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 10,593 | 9,842 | 31,418 | 29,492
Costs and Expenses: |  |  |  |
Cost of sales and services | 6,388 | 5,907 | 18,846 | 17,652
Cost of leasing | 1,587 | 1,473 | 4,763 | 4,378
Interest expense | 28 | 30 | 84 | 88
Other segment items | 1,610 | 1,555 | 4,699 | 4,620
Total costs and expenses | 9,613 | 8,965 | 28,392 | 26,738
Earnings before income taxes | 980 | 877 | 3,026 | 2,754
Operating Businesses [Member] | Pilot [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 10,882 | 10,630 | 31,421 | 36,132
Costs and Expenses: |  |  |  |
Cost of sales and services | 9,881 | 9,453 | 28,175 | 32,903
Depreciation and amortization | 266 | 254 | 783 | 750
Interest expense | 53 | 69 | 174 | 246
Other segment items | 752 | 706 | 2,193 | 1,993
Total costs and expenses | 10,899 | 10,413 | 31,151 | 35,646
Earnings before income taxes | (17) | 217 | 270 | 486
Operating Businesses [Member] | McLane [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 13,191 | 12,723 | 37,967 | 37,656
Costs and Expenses: |  |  |  |
Cost of sales and services | 12,054 | 11,683 | 34,660 | 34,556
Depreciation and amortization | 50 | 50 | 146 | 149
Interest expense | 6 | 4 | 19 | 14
Other segment items | 914 | 845 | 2,631 | 2,499
Total costs and expenses | 13,018 | 12,578 | 37,437 | 37,204
Earnings before income taxes | $ 173 | $ 145 | $ 530 | $ 452

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